div#loading{
    display: none;
    margin:100px auto;
    width:4px;height:4px;border-radius:2px;
    box-shadow:0 -12px 0 3px black ,/*上*/
                        0 12px 0 1px #333,/*下*/
                        -12px 0 0 1px #333,/*左*/
                        12px 0 0 1px #333,/*右*/
                        -9px -9px 0 1px #333,/*左上*/
                        9px -9px 0 2px #333,/*右上*/
                        -9px 9px 0 1px #333,/*左下*/
                        9px 9px 0 1px #333/*右下*/;
    animation:loading 1.2s linear 0s infinite;
    -webkit-animation:loading 1.2s linear 0s infinite;
    -o-animation:loading 1.2s linear 0s infinite;
    -moz-animation:loading 1.2s linear 0s infinite;
}
@keyframes loading
{
    from {transform:rotate(0deg);}
    to {transform:rotate(360deg);} 
}
@-webkit-keyframes loading
{
    from {-webkit-transform:rotate(0deg);}
    to {-webkit-transform:rotate(360deg);} 
}
@-o-keyframes loading
{
    from {-o-transform:rotate(0deg);}
    to {-o-transform:rotate(360deg);} 
}
@-moz-keyframes loading
{
    from {-moz-transform:rotate(0deg);}
    to {-moz-transform:rotate(360deg);} 
}